Telephone system



Feb. 16, 1937. w. M. BEAUMONT 2,070,642

TELEPHONE SYSTEM I Filed March 25, 1934 3 Sheets-Sheet 1 INVENTOR W. M. BEA UM ON 7' A TTORNE Y Feb. 16, 1937. w U T 2,070,642

TELEPHONE SYSTEM Filed March 23, 1934 3 Sheets-Sheet 2 FIG. 2

INVENTOP W. M. BEAUMONT ATTORNEY Feb. 16, 1937. w BEAUMONT 7 2,070,642

- TELEPHONE SYSTEM Filed March 23, 1934 I 3 Sheets-Sheet 3 i INVENfO/P W. M. BEA UMON A T TORNE) Patented Feb. 16, 1937 UNITED STATES PATENT OFFICE,

' TELEPHONE SYSTEM Application March 23, 1934, Serial ,No." 716,926

13 Claims.

"Thisinvention relates to telephone systems and more particularly to intercommunicating systems of the type which provide for: trunk connections'to anvoutside exchange or central office.

The object: of this invention is to provide the subscribers "of .an intercommunicating system ==with facilities for establishing one or more telephone connections with an outside exchange,

either central oflice or private'ibranch.

This objectyis attained in .accordance with .a :feature of the invention by the provisionrof switching equipment :at each substation by means'of-wwhich aany subscriber of an intercom- :municating system may aanswer or originate a central office. call.

Another feature nof the 2 invention resides in a novel circuit arrangement-which prevents certain subscribers. of an. intercommunicating system from interfering with or seizing a central office line after one of certain other subscribers =has the, line in use, either in answeringan incoming call or originating an outgoing call.

-Stil1 another-feature -.of' the invention is-embodied in .a circuit ,arrangement whereby certain subscribers of an intercommunicating system may cut off certain other subscribers, but not each other.

A further featureiof the invention is found in anarrangement of"circuits whereby a subscriber anay answer a-ca'll incoming over a line circuit from an outside exchange, hold the connection :and communicate with a secondsubscriber, on an intercommunicatinguline and whereby the second subscriber may release the holding connection and associatehis own telephone with the line. circuit.

Theseand other features of the invention will .be readily understood from-the following detailed description made with reference to the accom- ,panying drawings in which:

--Fig. lshowstwocentral ofiice lines incoming 'toua :subscribers-station and: terminating at a central -ofiice;

Fig. 2 shows a master station, such as a residence living room and switching equipment indi- :vidual thereto for associating the substation equipment with either of the central office line circuits of'Fig. 1;

Fig. 3- represents a substation, such as a residence'kitchen, and switching equipment individual thereto for associating the substation with but one of the central oflice line circuits;

Fig. 4 discloses a substation, such asa master 'bedroom,, and sw tch ng equipment individual thereto for associating the substation with either of said central office line circuits; and,

Fig. 5 represents a substation, su'chas a, garage, and switching equipment for associatingjhe substation with but one of the centralnoflicelinecircuits. a

"Central ofiicewall incoming-on lined!) C'aZZ answered-atstation A Assuming the master of the house is available- .12 and located in the living-roomsat the time the ringer H is sounded, he would proceedrtoanswer the call by actuating key l2 'whichi is..individual to line 10 and remove the handset from its switchhookat station'A. -It "is'toz'be understood that the ringers II and 2| associated With --lines l0 and 20, respectively, are distinctively :pitched soas to enable the person answering the call to determine which line the call is'on.

Upon removal of the handset at station A andcg the actuation of key l2, relay l3 operates ina circuit extending from grounded battery, lower winding of relay I 3,'conductor l4, frontcontact .of-key-l2, to ground by way of the contacts I5 of thehandset switchhook at station A. At: its 4-3 outer lower armature and front contact, relay I3 short-circuits the line I0, to prevent excessive' clicks being induced in the receiver atw stationA. At its inner lower armature and front contact,-relay 13 establishes a circuit extending from: grounded battery, outer armature and back contact of relay l6, conductor l1, conductor-'l8, W-inding'of relay [9, to-ground 0n the inner lower armature and front contact of relay l3. Relay l9 operates in this circuit.

At its inner upper armature and front contact relay I3 connects its own upper winding in circuit with the holding key 30 and at its outer upper armature and front contact closes a cir- Y cuit to busy lamptl which is associated with the stationA. This lamp, however, does not light at this time owing to the operation of relay l9.

-Relay. l9, operated, connects the talking circuit through to the subscriber's set by way of its upper :outerand lower middle armatures and front contacts and conductors 32 and 33. At its lower innermost'armature and front contacts, relay I9 closes part of the operating circuit of relay 34 by way of conductor 35. This circuit is open-at holding key 30. At its lower armature relay [9 opens the circuit to the'busy signal 3| and at its upper inner armature and front contact, establishes an energizing circuit for the cut-off relay l6 by way of conductors 36 and 41 and also establishes a locking circuit for itself which'is under the control of relay l3 which is held operated by the actuated line key 12 and switchhook at station A.

Cut-017 feature Cut-oft relay I 6 operating removes, at its arma- "tures and back contacts, battery from conductors "l1 and 31, thereby rendering the line relay38, associated with the kitchen'station B, inoperative should line key 50 be operated at this station in an attempt to answer the incoming call. By this means, station A is provided with a lockout feature 7 by virtue of which no other station normally havever effect the release of relay I 9 as this relay is now looked under control of relay l3.

Relay l6 at its inner armature and front contactcauses relay 52 to operate in anobvious circuit. Relay 52, operated, opensthe short which had, been placed across the line II] by the operation of relay l3. Relay 52 is slow operating in order to insure a good connection at the contacts of relay l9 and maintains the connection of station A to the line l0 before the short is removed.

The subscriber at station .A is now ready to converse with the calling party, all other stations such as station B of another group being locked out from association with the line I0.

Originating call from substation A the handset on its switchhook.

In case the call incoming over line I0 is answered at station A and is intended for someone located in the bedroom station C, the party at station A will operate the holding key 30 which releases key l2. This insures relay I3 being held operated when the ground at key I2 is removed from its lower winding. Relay !3 LS HOW 1 5 receiver at this time.

.which in turn. releases relay 52'.

leased, also opens the lower winding of relay 59.

erate over an obvious circuit.

1 operated to ground at the handset switchhook contacts by way of the holding key 39.

Holding relay 34 now operates in a circuit extending from grounded battery, right-hand winding of relay 34, conductor 55, lower innermost armature and front contact of relay l9, conductor 35, to ground by way of the closed contacts of key 30 and the handset switchhookcontacts at station A.

Relay 34 in operating establishes an obvious circuit for relay 56 and places a short across line In to prevent excessive clicks being induced in the At its left-hand armature and front contact, relay 34 locks up under control of relay 5! to insure the holding circuit functioning in case the holding key 30 is momentarilyoperated.

At its contact 58, relay 56 opens the line H) towards the station A and at itsarmature and front contact bridges relay 59 across the line In causingthis relay to operate from central oflice battery. Relay 59, operated, establishes an obvious energizing circuit for relay 51.

When key 30, which is non-locking, is released, relays l3 and 34 release. Relay 34, released, causes relay 56 to restore to normal whereas relay --I3, released, causes relay I9 to release. Relay 56 may release before relay I9 releases which will close a circuit through relay 10 which relay may 5 a operate momentarily and, in turn, may release relay 59. Relay 51, which is slow to release, will not release under this condition, thus preventing the opening of the bridge acrossthe line It].

Relay l9, released, opens the talking circuit to the station A and releases the cut-off'relay I6,

Relay '56, re-

7 Transferring calls When a call is to be transferred, the line I 0 must be held as justdescribed by actuating the holding key 30, otherwise the line will be momentarily opened which may cause the call to be lost. This applies to either an inward or an outward call.

To transfer the call on line I!) from station A to station C, the party after having actuated the holding key as just described now actuates keys Hand 12. Key 12, operated, causes relay 13 to operate by way of conductor 14 to ground by Way of the closed contacts of key 12 and the normally closed contacts of keys 54 and I2- and the handset switchook contacts at station A.

At its upper inner armature and back contact, relay 13 opens the circuit to buzzer 15 located at station A. At its two outer armatures and front contacts relay 13 connects the talking leads 32 and 33 to station A with the intercom! municating line 16.

The operation of key H causes relay 1! to 0p- Relay 11 applies ground to all the buzzer leads with the result that the buzzers 18, 19 and at stations B, C and D, respectively, are sounded. By the employment of a signaling code the party at station A may be informed that she or he is being signaled from another station. Either code signaling or selec-- tive signaling may be employed without departing from the spirit of the present invention.

In response to the operation of buzzer 19 at station C, the party thereat actuates the key 9| and removes the receiver from. its switchhook whereupon relay 92 operates in a circuit extendingfrom grounded battery, winding of relay 92, @Qnduotor 93, closed contacts of key 9|, normally closed contacts "of keys1'94 and 5I,:.to:'ground:at

the receiver switchhook contacts.

Relay F292 operated, opens 2 the' circuit 'to hu- 7 zer' 19:.andconnects the subset at station C' to theintercommunicating line 1 6. Therparties at with the outside party, the line key-5| will-be perated. -This causes relay 95 to operate in a circuit extending from grounded battery, lower winding of relay 95, conductor 96, right hand contacts of key to ground at the receiver sw-i-tchhook contacts'at-station C.

'The'operation of key 5| releaseskey9I whereupon relay 92 releases,- disconnecting the tele- "phone set at station C from the intercommunieating line 'l-fi.

"The operation of relay- 95 causes 're1ay'39 to operate in the same manner 'as doesthe operation of relay l3 cause relay [9 to operate as' already describedyandrtelay '39 performs the same function as does relay i9.

When the line It is closed through to station C by the operation of relay 39, relaylll, which is included in the talking circuit, operates, causing relay 59 to release'by short-circuiting the upper winding of this 'relay. Relay59,released, causes-relay 5'! to releasewhich in turnreleases relay 19 by short circuiting its winding. "The release of the relays just "described releases the holding connection establishedfby the party at station A and cuts through'the party at station C to the central ofiice.

"The party A, of course, 'wouldreplace the handset and restore key 12 upon being informed that the party" at station'C'wouldtake over the call.

Upon completion of the call' the .party at Statio-n C replaces the 'receiver'on'the switchhook whereupon all operated relays restore.

As set forth in thedrawin'gs, the stations A and C are to be considered as one type ofgroup, whereas stations B and D are to. be considered as another type. This is done merely to illustrate the flexibility of the system and to show howa station of one group may cut on" stations of. another group but not stations of the same; group. For example, the particular disclosure chosen by applicant illustrates how stations A. and C of the same group out off otherstationssuch asstation B, normally having .access to'thelline in, but do not cut ofi each other. i

. As described in connection with the answerer initiation of a callby the party. at stationA over line 10, relays l3 and .I9 operated, .the latter causing cut-offrelay l6.to operate. causing batteryto be cut off from .the conductors. I! and 31 which constitute linksin the original energizing circuits for relays l9 and 39 and, respectively. It will be noted that whenrelay; l9 operated as a result .of a circuit connection to line l flbeing established by the-party-atstationA, this relay locked up to battery associated with the contact 4! thereof. This battery is connected to con- .ductor H by way of conductor I8, the conductor H leading directly to the windingvof relay 39 at station C. Itfollows, therefore, thatshould the party at station vC attempt'to cut inon line It] when station A is associated therewith; he would be able to do so by virtue ofthe'fact that relay 39, individual to station C would operate from battery, back contact and lower outermost armature as relay38; upper outer armature and front 'throughthe filament of lamp d3.

- batteryassociated with the contact I: of relay l9 when relay- 95 operated as a consequencebf the actuation of key 5! at station C and the removal ofthe receiver thereat. Relay 39 in operating connects the telephone-set at station C across-the -line [0 in the same manner as does relay l9 connect the telephone set at station A across the line 10. It is readily seemtherefore, that though I station A cuts off station B of 1 another group .of stations it docsnot cut off station "C which is lIO of the same group.

"In establishing a connection, however, with line it] when this line is-idle, the relay 39 finds'bat- 'tery on conductor ll by way of the outer armature and back contactof thecut-ofi relay Hi. It

is only when the line H! is in use by the party atstatio-n A or-a station of the same group that the battery'at contact M of relay IQ, for example,

is substituted for the battery associated with the outer armature of relay=l6 "for the purpose of permitting relay 39/for example, to be operated should the'party-a't station C desire to get in on line [0 whenthis line is in use. a

" Should the line it] be in use by the party at *stationC the party at station A is not prevented from getting in on the line. The'battery at contact 42 of relay 38 provides the energy for relay l9 in this case, relay it having been operated as a consequence of the operation of relay 39.

It is tobe understood that "the cut-off feature is available on calls on line 20 as Well as on line It.

Should the party at station B attempt to establish a central office connection on line=f-0 when this line is in use, relay 42 would operate as a consequence of the actuation of key50 and the removal of the receiver from its switchhook at station B. Relay 38, howevenwould not operate as battery has been removed from conductor 37 as a result of the operation of relay I'6 incidental to the seizure of linelfi at a station of another group. In this case, the busy lamp at at station B is lighted in'a circuit extending from grounded 45 contact of relay "42, conductor '44, to ground The lighted lamp 43 indicates to the party at station B tha the line I0 is in use.

Non-cut-ofifeature Stations, such as stations BandD-of one group may be cut off by other stations, such as stations A andC of another group but cannot cut on these other stations.

-When the party at station B, for exampleremoves the receiver from itsswitchhookand'a-ctuates key 59, the relays-t2 and "38 operate in the 'same'manner as do relays-l3 and i9 as described in connection with a' call originating or answered at station A. It will be noted now that --'where relay 19 caused cut-0fif relay i6 to opera-te'in the first description, relay [6 isnot a'fiected by the operation of relay 38 in this case. Hence, relays, such as I9 and 39pmay operate should the parties at stations Aand/or C attempt to establish a connection with line H] when this line is in use We. party of another group suchas the party at station B. In this cas-a'however, where the partyat station B is the first to establish a connection with line l0, station B is 'not disconnected from the line by a subsequent seizure of the lineby a party at-either-station A or C until the party at station B'replaces the receiver on the switchhook This is due to thefact that relays 42 and 3B are locked up to ground at the receiver switchhook contacts at station B. This prevents the cut-offstation, such as station A or station B, from cutting off the connection.

Intercommunication between any of the stations of the system is possible. .I'he operation of keys 12, 97 or 9| at stations A, B or C, respectively, or the removal of the r'eceiver at station D will associate the respective telephone sets with the. intercommunicating line 16 and signaling may be efiected in the manner previously described in connection with the transferof a call from station A to station C.

In the circuit arrangement disclosed applicant showstwo central office lines and 20 and four.

stations A, B, C and D, the stations A and C having access to both lines, station B having access to line IE only and station D having access to but line 26 and also discloses a'system wherein stations ,A and C may cut ofi stations B and D but-not each other, stations Band Dbeing arranged to be cut ofi by stations A and C but not to, cut off these stations. It is readily apparent from the foregoing description that stations B .and/orD-rnay be given access to both central office lines and be provided with the cut-off features attributed to stations A and C in the disclosure of this application if desired.

What is claimed is: 1 1. In a telephone system, a plurality of .sta-

tions, a line circuit normally accessible to each of said stations, a relay for each of said stations,

means at each of said stationsfor causing the;

energization of, its respective relay to effect the seizure of said line circuit and a relay operating upon the seizure of said line circuit atone of said stations for rendering said line circuit inaccessible to certain other but not all other of said stations.

2. In a telephone system, a pluralityiof stations, a line circuit normally-accessible to each of said stations, a relay for each of said stations, means at each of said stations for causing the' energizationof its respective relay to effect the seizure of said line circuit and a relay operating in response to the seizure of said line circuit by one of said stations for rendering the station'reative in response to the seizure of said; line -circuit by a station of said first group forpreventing the subsequent operation of the station relays of said second group in response to the actuation of their respective energizing means.

4. In a telephone system, agroup' of stations, a second group of stations, a line circuit 'normally accessible to the stations of both said groups, a relay for each of said stations, means at each of said station's'for completing an energizing circuit for itsrespective relay to effect its operation, the operation of said relays eifecting the seizure of said line circuit, and a-relay normally controlling the. energizing circuits for said station relays and operative! only upon the seizure of said line circuit by a station of said first group to prevent the completion of an energizing circuit for the second group.

station relays of said 5. In a telephone system, a. first group of stations, a second group of stations, a line circuit accessible to all the stations of said groups when said line circuit is idle, means responsive to the seizure of said line circuit by a station of said first group for rendering said line circuit busy to the stations of said second group only, and

means at each station of said second group for indicating the busy condition of said line circuit,

said means operating in response to an attempt to seize said line circuit at a station of said second group. 1

6. In a telephone system, a group, of stations, a second group of stations, a line circuit normally accessible to the stations of both said groups, a relay for each of said stations operative in response to the seizure of said line cir-' cuit, a relay associated with said line circuit and normally controlling the operation of all said station relays, said relay operating in response tothe seizure of, said line circuit by a station or said first group for rendering the station relays of said second group inoperative, and means controlled by the operated station relay of said first group for maintaining the, other station relays of said first group operative.

7. In a telephone system, a group of stations,

a secondgroup of stations, a line circuit, a relay for each station of both said groups for efiecting the seizure of said line circuit, a common relay,:

the normal energizing circuits for each of said 7 station relays being under the control of said common relay and means controlled by a, station 535 relay of said first group for operating said comf 'mon relay upon the seizure of said line circuit by a station of said first group whereupon the control of the station relays of the other stations of said first group only is transferred to the operated station relay of said first group;

8. In a telephone system, a group of stations, a second group of stations, a line circuit normally accessible to each station, a station relay individual to each station and normally controlled thereat for efi'ecting'the "seizure of said line circuit, anda line relay operable from the stationsof said first group only, for removing the control of the station relays of said second group from their respective stations whereby said line circuit is renderedinaccessible to the stations of said second group when said line relay is operated.

, 9. In a telephone system, a group of stations,

a second group of stations, a line circuit nor mally accessible to each of said stations, astation relay for each station for effecting the seizure of said'line circuit, a line relay, an ener-' gizing circuit for each .of said station relays under the control of said line relay, circuit clos- 7 ing means at each of said stations for completing the energizing circuit for its respective station relay, the operation of said means at the station's} of said first group also causing the operation of said line relay whereupon the station relays of said second group are rendered inoperative from their respective stations.

10. In a telephone system, a group of stations, a second group of stations, a line circuit normally accessible to all of said stations, a station relay for each station for effecting the seizure of said line circuit, an energizing circuit for the station relays of the first group of stations, an

energizing circuit for the station relays of the second group of stations, a line relay controlling both said energizing circuits and means at each station of said first group for operating its respective station relay and said line relay, the operation of said line relay opening both said energizing circuits and the operation of said station relay preparing a substitute energizing circuit for the other station relays of said first group whereby said line circuit is maintained accessible to the other stations of said first group and rendered inaccessible to the stations of said second group.

11. In a telephone system, a plurality of substations, a line circuit, signals located in the vicinity of said substations for indicating an incoming call over said line circuit, means at each of said stations for answering an incoming call,

means for establishing a holding connection for said line circuit, said means being operable from the station answering the call, and means operable at a second station for releasing the holding connection established by the means operable at the answering station and for connecting said second station with the line circuit.

12. In a telephone system, a plurality of substations, a line circuit, signals located in the vicinity of said substations for indicating an incoming call over said line circuit, means at each of said stations for answering an incoming call, means for establishing a holding connection for said line circuit, said means being operable from the station answering the call, means for maintaining the holding connection independent of said last mentioned means and means at a second station for releasing the holding connection and connecting said second station with said line circuit.

13. In a telephone system, a line circuit, a first station, a second station, both said stations normally having access to said line circuit, a signal at said second station, means controlled from said first station for seizing said line circuit and for preventing the seizure of said line circuit by said second station, and means controlled at said 7 

